| 摘要 |
A combination oil ring prevented from freeze up of the side rails and spacer expander, that is, a combination oil ring of the present invention provided with a top and bottom pair of side rails 11 and 12 and a spacer expander 13 having large numbers of top pieces 14 and bottom pieces arranged separated in the axial direction and circumferential direction and alternating in the circumferential direction, connecting pieces 16 connecting adjoining top pieces 14 and bottom pieces 15, and ear parts 17 and 18 formed rising up at the inner circumference side ends of the top pieces 14 and bottom pieces 15 for pushing against the side rails 11 and 12, in which combination oil ring 10, grooves 19 and 20 are formed in at least one surfaces of top surfaces of the top pieces 14 and bottom surfaces of the bottom pieces 15, and through holes 17a and 18a by which the grooves 19 and 20 are communicated are formed in the ear parts 17 and 18. |
